#im sorry this is so incomprehensible | Explore Tumblr posts and blogs

userm4x · 1 year ago

Text

Physics for rookies! What is Adrien Newey cooking in there?

Here is the culmination of my research into the physics behind F1, my own knowledge from GCSE physics, and what I have gleaned from my very patient friend who took A-Level physics. This is about as in-depth as I can understand in hopefully simple and fun explanations. I've used the RB19 as my example model because I don't think I'll ever truly be over her.

The basics!

Because a lot of this primer uses language that you might not remember or sort of vaguely understand, here's some basic explanations of physics stuff that comes up:

Energy: this is defined as 'the ability to do work' - how much capacity you have to do something, such as move, or react! There are several different forms of energy: kinetic (movement), thermal, light, gravitational, electrical, sound, chemical and nuclear. Energy can be transferred between these different forms - for example, some of the light energy produced by light bulbs is transferred into heat, which is why they are hot to touch. It can also be transferred between different objects that are touching. This can cause other objects to move, such as water rippling, or other objects to begin to heat up, like a pan on a stove.

Particle: in science, this refers to an extremely small piece of stuff, most commonly a molecule or an atom. Although the air seems invisible to us, it is actually made up of various gases and other types of particles. We don't feel the pressure these particles exert on us because we produce enough energy to move through them without them bothering us, and we don't see them because they're so small and spread out!

Pressure: the physical force exerted on or against an object by something coming into contact with it. In this primer, this mostly refers to the pressure caused by the particles that make up gases, which collide with the things around them as they move around randomly. Pressure can be relative in the same volume - high pressure areas have more particles in the same volume than low pressure areas, which have less. Pressure can be changed by increasing the volume - more volume with the same amount of particles equals a lower pressure.

But wait ... physics matters in F1?

The physics behind F1 cars dictates how the team develops their cars! Understanding why the updates they add to the car work why they do helps them to develop further changes, or to make adjustments according to the race weekend. There are a few different forces teams need to think about during development and set-up:

Drag

Downforce

Ground effect

Some cars have high or low drag - what does that mean?

Simply: how much drag a car has directly translates to how easily the car moves through the air. The more drag the car has, the less energy goes into acceleration, as more energy goes into moving the particles in the air out of the way. Complicatedly:

The energy of an F1 car produces different types of energy, the most obvious ones being kinetic, thermal, and sound. Most of the kinetic energy the car produces goes into making it go fast, but since some of the particles that make up the air are touching the car, some of that kinetic energy has to go into pushing those particles out of the way so the car can move past them. This makes the car less efficient, as less of the energy produced is going toward its intended purpose: zooming! The horizontal force the car experiences caused by these air particles pushing on it as it moves them out of the way is called drag. There are a few different types of drag that an F1 car can experience:

Skin Friction Drag: what it sounds like! Some particles in the air have qualities that make them attracted to surfaces, such as the wings or chassis of an F1 car. These particles can stick to the car, and then become attracted to other particles that are free in the air. These attractions can build up layers of particles. The attraction between particles attached to the car, and particles in the air increases the amount of energy the car has to use to move them out of the way

Form Drag: this just refers to 'normal' drag - the force caused when an object pushes the particles in the air out of the way. The shape of an object can affect the amount of form drag it experiences. The smaller the area moving through the air, the less pressure it experiences, and therefore the less drag experienced

Induced Drag: this is a type of drag caused by a second force an F1 car experiences, downforce. Downforce creates an area of high pressure and an area of low pressure. The particles in the air try to even this out by moving from the area of high pressure to the area of low pressure. This happens most around the front and rear wings of an F1 car. However, it's unavoidable, because downforce is vital to the function of an F1 car!

If an F1 car is high drag, this basically means it is designed in a way that is not efficient for moving through the air, so it wastes loads of the energy produced by the engine. These cars often have huge speeds losses on straights when compared to low drag cars. Low drag cars are great at moving through the air! They have lots more energy left over to go into speed.

How do you make a car high or low drag?

F1 engineers use a few different techniques to reduce drag. Here are some of them:

Endplates: induced drag means that the air moving over the front wing and rear wing of F1 cars wants to go down underneath them, from the area of high pressure to the area of low pressure. Endplates stop them moving sideways over the plates, and instead keeps them moving in a straight line over the wings. On the front wing of the car, the endplates also reduce drag by directing air over the wheels of the car, and not into them!

Sidepods: remember how Mercedes refused to have sidepods, and then added them as an upgrade? Sidepods help to reduce form drag by directing the air flow in specific ways over the car. This also helps to increase downforce - they're kind of important!

Nose: F1 cars have super thin noses. This helps to reduce form drag - the smaller the area experiencing pressure as it moves through the air, the less energy is used!

DRS: the drag reduction system on an F1 car opens the rear wing during specified zones on each circuit. This removes the induced drag caused by the wing generating downforce, so the car gains around 10 extra km/h!

To see how these different components change how air is directed over the surface of the car, you can watch the tests teams often do early in free practice 1. During aerodynamic tests, they add neon paint to areas of the car and record how it spreads!

Most of these components are regulated by the FIA, but teams can design and adjust them within those regulations to get different effects to suit different circumstances. This can be why you see teams bringing different sidepods, or wings, to different tracks! Power circuits (e.g. Monza) refer to circuits where the speed of the car is most important to its performance. These circuits typically have a bunch of straights and slow speed corners, where downforce isn't useful, but reducing drag is!

What's downforce?

Simply: downforce is a term mainly specific to F1 that refers to the force that sucks the car down toward the floor when it moves. The more downforce a car has, the faster it can go! Complicatedly:

Downforce refers to the vertical force that a car experiences due to the particles in the air pushing downward on it. This happens when the car isn't moving, but also when it does! As the car moves and air flows over it, the particles in the air collide with the car and create pressure. Downforce is also sometimes called 'negative lift', as the opposite of lift occurs.

The amount of downforce an object experiences increases according to the square of its speed. This means that if you are travelling at 50 km/h, with 10N of downforce, and double your speed to 100 km/h, you increase the amount of downforce you experience to 40N (WARNING! MATHS: 50 x 2 = 100, 2² = 4, 10 x 4 = 40).

Teams want lots of downforce on their car for a few different reasons:

Downforce stabilises the rear of the car. This makes it easier for the driver to handle the car and predict what it will do

The more downforce you have, the higher the top speed of your car is

Teams want extra speed in medium and low speed corners. Because of the above principle, its actually easy to find extra downforce in fast corners! Medium and slow speed corners are the problems.

What's a ground effect? How does it work?

To generate more downforce, F1 engineers now consider the ground to be part of the system that produces different forces on an F1 car. This principle is called the ground-effect, and it can be used to produce ground-effect downforce. Ground-effect is also used to explain why planes float before they reach take-off speed!

In modern-day F1, most ways that are used to produce ground-effect are based off Bernoulli's principle. This principle refers to the effect that occurs when an object is lowered to the floor as air flows around it. As air moves between the object and the ground, it accelerates as the amount of space it has to move between them decreases. This causes pressure between the object and the ground to decrease, while pressure above the object stays the same - this creates an area of low pressure, and an area of high pressure. The object then experiences an overall downward force, which presses it toward the floor!

The area of low pressure underneath the car also works between the floor of the car and the track surface by trying to decrease the volume that the particles are contained in - it either tries to pull the track up towards the floor of the car, or pull the floor down toward the surface. This 'pulling' force acts as a vertical force, so it technically increases downforce!

How do you get extra downforce?

Anything that helps to either increase the pressure over the top of the car, or decreases the pressure underneath the car can help! The most common way engineers do this is by considering the entire car to be one big 'wing', but there are couple of methods:

The front wing: the front wing directs air close to the surface of the track up and over the body of the car, which increases the amount of air causing pressure over the top of it. This creates an area of low pressure under the front wing, and an area of high pressure above it

The skirt: the skirt around the floor of the car prevents air from entering underneath it from the sides. This stops the low pressure area underneath the car from being interrupted!

The flaps and fins: flaps and fins along the sides of the car force air into little spirals that create and trap a vacuum that 'seals' the edges of the car

The floor: the floor of an F1 car is covered in venturis - these are ducts that slowly expand toward their end. This both accelerates the particles in the air through the duct as they try to accommodate for the increase in space, but also decreases pressure under the car. The floor of the car is one of the biggest ways teams utilise ground-effect to increase downforce!

Ride height: adjusting the ride height of an F1 car refers to adjusting how low it sits to the ground. Decreasing the ride height increases downforce according to Bernoulli's principle. It is also one of the favoured ways to increase downforce, as it is one of the few that does so without massively increasing drag!

Sidepods: sidepods can be used to direct air flowing over the car toward the floor and into the venturis to increase downforce. Wide sidepods can also function in a similar way to the skirt of the car

Some of these components can be adjusted every race weekend to suit the conditions of the track. For example, the ride height can be adjusted, as can the angles of the front and rear wings. High downforce circuits (e.g. Monaco) are those where having a lot of downforce is advantageous. They are characterised by lots of corners, and very few, often short, straights. At these type of circuits, having low drag isn't super important - how attached to the floor you can get your car is!

Let's go porpoising! - Gunter Steiner

Porpoising refers to the rapid upward and downward movement of the body of the car as it bounces on its suspension. This is caused by the floor of the car being sucked too close to the floor, and the low pressure becoming problematic. It causes the air to stall underneath the car, which forces it to bounce up so the air underneath it can be released. This cycle continues over and over again, and you end up with porpoising!

The problem arose after the regulation changes for the 2022 season, when using the ground effect to generate downforce was allowed again! It dominated the way F1 cars were engineered throughout the 1970s and early 1980s, and then was disallowed after regulation changes. There were fears about cars losing the downforce generated from the ground affect, and then shooting off the track. The FIA reintroduced it in an attempt the reduce the effect of dirty air.

Porpoising became so wide-spread and severe among the teams that the FIA had to stage a technical intervention with a change to the regulations. The edges of an F1 car's floor have to be 15mm further away from the surface of the track than previously, which allows stalled air to be released and decreases the area of low pressure underneath the car. This appears to have fixed the problem! However, porpoising is still one of the more memorable parts of the 2022 season.

How does this help me understand what Adrien Newey is cooking in there?

I know that the title of the primer suggests that I do, in fact, know 'what Adrien Newey is cooking in there.' I regret to inform you that I don't. He's beyond all of us.

But, if you have any questions or want to chat more technical F1 stuff with me, my ask box is open and I'm happy to talk! Hope this helped :)

#seriously tho. sm1 needs to study adrien's brain i gotta know what that man is storing up there #and also tbh i do not fully understand bernoulli's principle or what a ground effect is bc there arent many simple and understandable #explanations out there. so if that part is incomprehensible im so sorry #f1 #formula 1 #f1 primer #f1blr primer #beth posts

93 notes · View notes